Impaired blood circulation in the lower limbs is a common health problem among the elderly and one of the most prominent complications of diabetes, called diabetic foot. A syndrome characterized by foot ulcers, often associated with infection, it is the leading cause of hospitalization and up to 30 percent of amputations. To reduce the likelihood of such highly traumatic consequences, scientists from Lithuania have worked together to develop an ultrasonic foot stimulation device that can non-invasively improve blood circulation in the lower limbs.
This innovative device was created through a collaborative effort of scientists from the Kaunas University of Technology (KTU) and the Lithuanian University of Health Sciences (LSMU).
According to them, the main focus is on improving solutions for the problem of large blood vessels through mini-interventional methods. However, clinical solutions for diagnosing and correcting minor vascular disorders, searching for effective and non-invasive methods, and their practical implementation are lacking.
Increasing prevalence of diabetes
Up to 40 per cent of patients who do not develop severe changes in the large blood vessels are treated with conventional symptomatic medications, often without treatment at all. They are simply attributing to psychosomatic symptoms without investigating the possible causes of such complaints. Then, the problem deepens, and often, the consequences become difficult to correct or irreversible.
Therefore, focusing on the consequences of microcirculatory disorders that are increasingly diagnosed, we wanted to find solutions and clinical methods for this problem and specifically try to help patients with diabetes."
Algimantas Bubulis, KTU senior researcher and one of the authors of this invention
In various European countries, diabetes affects between 3 and 7.2 percent of the population, and this is a gradually increasing trend. In Lithuania, about 100 thousand people suffer from this disease, and this number is expected to double in the next 10 years.
LSMU professor Vincentas Veikutis, who led the medical research on the invention, says that although diabetes is successfully corrected, complications caused by it, one of which is diabetic foot syndrome, remain a clinical problem.
Usually, due to impaired tissue circulation and progressive neuropathy, the tissues of the foot become insensitive and no longer respond adequately to trauma, leading to progressive ulceration, wound infection, tissue necrosis, and, ultimately, amputation.
As the ability to treat this pathology with drugs is limited, alternative and, in particular, non-invasive treatment methods, including the use of ultrasound energy, are becoming increasingly important.
"Ultrasound, as one of the therapeutic methods, has recently been widely used in practically all fields of medicine," explains Bubulis.
According to the scientist, this is determined by the wide range of applications in medical practice. The body's most diverse tissues and structures, bones, skin, muscles, and biological fluids, including blood, can be affected by it. Under the influence of ultrasound, it can reduce pain, spasms, and inflammation and also stimulate blood flow.
"Ultrasound through the retrograde neurogenic pathway can also activate central blood flow in the body's main blood vessels, which are closer to the heart and lungs. This further expands the possibilities of its therapeutic use," adds Dr Bubulis, a senior researcher at the KTU Mechatronics Institute.
Ultrasound affects not only tissues but also the nervous system
The device, developed and approved by scientists, uses particular piezoelectric elements to generate a broad spectrum of acoustic ultrasound waves in response to an electrical signal. Then, after selecting the appropriate parameters, the ultrasound is transmitted to the foot tissues and can stimulate blood flow in practically the entire leg.
"Vibrations caused by electric current flowing through the elements create acoustic waves. The waves pass through the skin and enter the deeper tissues, where they cause vibrations and increase the tone in the walls of blood vessels. It helps to improve the blood flow in the superficial tissues and modulate the activity of blood-forming elements: erythrocytes, leukocytes, and thrombocytes.
In this way, it is possible to regulate thrombogenesis, immune response, and inflammatory processes, which are essential for normal vascular and general tissue function," explains the KTU expert.
In addition, ultrasound waves can act on nerve structures, considering that all blood vessels have innervation and thus activate vascular tone in a vast tissue area.
"Diabetic neuropathy or nerve dysfunction, usually of ischemic origin, can also be corrected to a large extent using ultrasound of certain parameters," emphasizes Prof. Veikutis.
It should be noted that ultrasound's therapeutic effect on a person depends on physical parameters: wave frequency, power, and intensity. In this case, the developed device uses low-frequency ultrasound. Its operation is non-contact and non-thermal, which minimizes possible adverse events.
The invention has been granted both a Lithuanian and a European patent, marking a significant milestone. According to Dr Bubulis, after making a commercial prototype, this device can potentially revolutionize medical practice in rehabilitation hospitals and wards, preventive medicine offices, and nursing hospitals. Its portability, safety, and ability to correct a wide range of lower extremities of various circulatory disorders make it a promising tool for the future.
The device can be tailored for individual use with appropriate software modifications, making it a valuable tool for patients with diabetes and other peripheral circulatory disorders. It also holds promise for older individuals with chronic vascular dysfunction.
The KTU researcher adds that ultrasound with appropriate parameters could facilitate the focused integration of chemotherapeutic drugs in the desired location, avoiding general toxic effects on the body. "This could be an important, promising technological breakthrough in common medicine," upholds Prof. Veikutis.
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